Spark-arrester.



c. w. CROWELL.

SPARK ARRESTER. APPLICATION FILED APR. 6; I914. RENEWED JUNE 3.1915.

m; NORRIS F'ETERS co.. PNOTDJJIHO WASMING mu, m c

Patented June 12, 1917.

CHARLES W. CROWELL, OF BISCOE, NORTH CAROLINA.

SPARK-ARRESTER.

Specification of Letters Patent.

Patented June 12, 1917.

Original application filed April 5, 1911, Serial No. 619,051. Divided and this application filed April 6, 1914. Serial No. 829,920. Renewed June 3, 1915. Serial No. 31,971.

To all whom it may concern:

Be it known that 1, CHAnLns 1V. CRownLL of Biscoe, in the county of Montgomery and State of North Carolina, have invented a certain new and useful Improvement in Spark-Arresters, and do hereby declare that the follmving is a full, clear, and exact description thereof.

My invention relates to steam boilers and considering it in its entirety, more particularly to locomotive steam boilers, and briefly, but not exclusively stated, my object is to arrest, or prevent the discharge of sparks and unconsumed gases or products of combustion by securing the extinguislr ment of sparks and causing the further com bustion of the incompletely consumed gases, or matters, thus economizing in, or getting a greater efliciency out of the fuel; and to provide a construction which will present 110 high extensions or projections from the top of the boiler and thus render possible the passage of the locomotive through tunnels, under bridges or other overhead structures, which projections or extensions on the top of the boiler might encounter, and to this end and to secure other advantages which will be evident when my invention is described more at large hereinafter in the specification, my invention consists in the construction substantially as hereinafter specified and claimed.

The invention forming the subject hereof is illustrated as embodied in the boiler forming (519,051, filed April 5, 1911, and is divided out of that application pursuant to a re quirement of the Patent Office and I, therefore, illustrate the present invention as similarly embodied as'in that application, but without limiting myself to its embodiment in that particular construction of boiler, or to any particular construction of I boiler.

In the accompanying drawings Figure 1 is a longitudinal vertical section of such a boiler as that illustrated in my application above mentioned with my invention which forms the subject hereof adapted thereto;

Fig. 2 is a front elevation thereof;

Fig. 3 is a cross section on the line 3 3 of Fig. l, and drawn on a larger scale than the other figures.

A brief description of the general conthe subject of my application No.

struction of the boiler illustrated is all that is necessary herein, it being enough to explain that it comprises a fire box A having below the grate B an ashpit C with groups of fire tubes, or heating lines D that extend from the firebox flue sheet forward to deliver the products of combustion to a smoke box E at the front end of the boiler and finally after they pass rearward and then again forward delivering them to a short pipe, or flue 1.0, which opens through the top of the boiler and which alines vertically with a nozzle 11 that receives exhaust steam through an opening in the bottom of the boiler so that by means of such exhaust steam there is a forced draft or blast upward through the pipe, or tube 10.

From the pipe, or tube 10, the escaping products of combustion enter the first of a series of chambers, which for convenience I shall speak of collectively as the spark ar roster, which extends horizontally rearward on the top of the boiler with a discharge opening, or outlet 12 on the top of the boiler at or near midlength thereof so that in reality I provide what in effect is a horizontal stack that extends rearward and has its discharge or outlet at its rear end. Besides lying on the top of the boiler said horizontal stack extends downward over each side of the boiler saddle-wise so that its form, or shape in the main is that of an are, or a truncated crescent, the horns of the crescent being cut off, or flat and not pointed as may clearly be seen by reference to Figs. 2 and 3 of the drawings. By giving the stack the saddle shape so that it extends down over the boiler on each side thereof, an ample area for the stack is provided so that there will be no back pressure in the stack which might exist were its area in cross section too small. This enablesthe employment of my invention with very large boilers, for it gives ample area without requiring such projection of the stack above the top of the boiler as would result in the stack striking bridges, tunnels, etc. The bottom plate 13 of the stack in cross section conforms to the curvature of the contiguousportion of the boiler, and, as indicated in dotted lines in Fig. 1, it extends horizontally from the front and then inclines upward and rearward narrowing as it approaches the rear toform the contracted outlet, or discharge 12 and at its extremerear portion it is curved upward and reaches at its rear extremity to a level above the top sheet, or plate 14;, so that in the forward travel of the locomotive (if it be a locomotive boiler) air will impinge, or strike upon said curved surface, or lip and aid the draft through the stack. The top plate 14 extends preferably horizontally, and it valso is curved in cross section and between it at its forward end and a plate 15 which curves from a point at the front side of the pipe, or tube 10 upward and rearward, is an opening that forms an air inlet by which, when desired, a current of air may be caused to enter the stack at the front thereof from the onward movement of the locomotive and thereby create or augment a draft through the stack. A valve, or damper 16 is provided in such passage at the front end thereof-by which said passage may be opened, or closed at will, a connecting rod 17 being provided that runs to the locomotive cab so that said i damper may be manipulated to control the draft. A plate 18, which extends from the damper 16 rearward provides a conduit, or passage 19 for air admitted by the openmg of the damper, said plate 19 terminating substantially at midlen'gth of the stack. The plate 15, or an extension 20 thereof, is carried downward and rearward toward the top of the boiler and thus subdivides the stack into a forward compartment 21 having a contracted outlet 22 at its ,rear end which delivers the products of combustion into a second or intermediate chamber .23 which is formed by a plate 24 that is spaced be tween the bottom plate 13 vand the top plate 14 and at its rear end reaches the bottom plate 13 and from said second, or intermediate chamber 23 there is at its forward end a discharge opening, or outlet 25 which leads into a third, or last compartment 26 which terminates in the stack outlet 12. Each of the outlets 22 and Y25 may be varied in size by similar adjustable plates, the outlet 22 having such a plate 27 and the outlet 25 having such a plate .28, each being secured by bolts so as to permit adjustment toward and from the ends of the respective outlets and each cooperating with an opposite inclined surface so that the effect of such adjustment is to contract, or enlarge the area of the outlet. At about midlength of the intermediate compartment 23, it has in its top plate 24: an opening 29 that establishes communication with the third or last stack chamber 26, such opening being controlled by a damper 30, which by means of a rod 31 that extends to the cab may be opened and closed from the cab and thus communication is established between the intermeinto the last chamber 26 other than and in addition to the passage through the outlet 25. To the pressure-receiving opening 29 a rearwardly extending conduit, or passage .32 connects with the forward end of the inor other unconsumed matters that are heavy enough will be conveyed from the stack to the ashpit that is below the grate in thefire box and either accumulated therein, or if light enough to pass upward will enter the firebox A and be subject to the heat thereof and in whole or in part consumed. Such matters as may pass to the rear of the opening 33 and which are heavy enough to fall to the bottom of the stack, will, by reason of the downward and forward inclination thereof to the opening 33 slide to the latter and thus find their way into the pipe 34 and will pass on to the ashpit. Each pipe 31 has, near the ashpit end a damper 35.

The operation of my invention will be readily understood from the drawings, and description that has been given. The unconsumed and escaping products of combustion will pass from the pipe or tube 10 into the first chamber 13 and by the arched cover 15 thereof will be directed rearward and downward and pass from said chamber 21 into the intermediate chamber 23 and then will be directed forward and will pass therefrom through the forward outlety25 thereof (any excess pressure being taken care of by manipulating the damper 30, as has already been explained) and from the outlet 25 they will enter the forward end of the third, :or last chamber and then be carried'rearward and the blast with the unconsumed products of combustion reduced to ;a minimum will finally emerge through the stack outlet 12. Inasmuch as the exhauststeam enters the pipe, or tube 10 with the escaping products of combustion and mingles therewith in said tube and also in the first chamber 21, it will be seen that ample opportunity is afforded by the intimate contact of the steam for the extinguishment of any sparks. If, for any reason, it is desired to supplement the draft produced by the exhaust steam, or under conditions when :steam is not being used, as when the locomotive is coasting or running without steam power, the damper 16 controlling the draft passage 19 may be opened so that a draft through the stack is produced by the onward movement of the locomotive. Thus, it isunnecessary to use steam merely for the purpose of producing the draft through the stack, and 139 hence, economy in the operation of the boiler is secured. It will be seen that by my horizontally extending stack and with the circuitous route of the products of combustion therethrough, ample opportunity is afforded for extinguishing sparks; for capturing, or saving combustible products of combustion which may be utilized by being again passed to the firebox; back pressure in the exhaust pipe or tube 10 is prevented and the escape of cinders is prevented and they are conveyed to the ashpan where they can be conveniently disposed of. The exhaust from the pipe, or tube 10 after being directed downward and rearward by the curved front plate 15 of the front chamber divides so that half, or substantially half of the current produced passes rearward on either side of the boiler and a large portion thereof enters and passes through the pipe 3 1 and is conveyed to the ashpan, while the remainder on each side of the boiler travels rearward and upward to the rear end of the intermediate chamber and thence passes forward, and, as has been explained, enters the third or last chamber from which the current or draft makes its exit, and being directed upward and rearward, avoids the envelopment of the engine and carsby escaping heat and gases when passing through contracted spaces, such as under bridges and through tunnels. The envelopment of the boiler by the stack in itself diminishes loss of heat by radiation from the boiler and the boiler also gets the benefit of the high temperature of the contents of the stack.

An important advantage from the use of the pipes leading from the spark arrester, or stack to the ash pit is that the hot gases, sparks, cinders and other unconsumed matters passing through and discharging from said pipes will mingle, or mix with the air entering the ash pan through the usual openings and will heat or raise the temperature of that air before it enters the fire, thus avoiding the chilling effect of admission of cold air to the fire box and the admixture of air with the combustible matter coming from the pipes promotes their combustion. By means of the dampers 35 in the spark pipes 84 the draft through those pipes into the ash pan may be regulated and any desired amount of gases and exhaust steam may be admitted to the ash pan. The dampers 35 are preferably operated from the cab.

It will be observed that by running the pipes 34 into the ash pan, I penetrate but a single wall, whereas, entry of the pipe into the fire box would involve penetrating two walls and passing through the water space with the necessity of a special construction that would protect against leakage of the water in the boiler. As will be seen by reference to the drawings, and in particular 21, splits or to Fig. 1, it will be seen that the discharge end of the pipe 34 is below the mud frame and below the outside boiler shell. Besides the structural advantages of my construction it will be seen that the unconsumed combustible matters that are discharged from the pipes 34 reach the ash pan at a point where the most efficient mingling thereof with the air entering the ash pan is effected to the end that their combustion is promoted and the incoming air is warmed before it passes through the grates into the fire.

Having thus described my invention what I claim is 1. A boiler having an outlet or stack arranged horizontally on the top with its discharge end at the rear and communicating directly to the atmosphere at the rear, a horizontal passage extending from the front end of the stack where it opens directly forward and reaching partially through the stack, through which passage air may be directly passed from the front of the stack, and a damper for controlling the movement of air through said passage.

2. The combination of a boiler having an outlet at its front end, and a stack upon the upper side of the boiler reaching from said outlet rearward and having a discharge opening leading directly to the atmosphere at its rear end, said stack having a downwardly and rearwardly extending plate that forms with the contiguous bottom of the stack, a contracted outlet, and a chamber into which said outlet discharges having an outlet above said plate.

3. The combination of a boiler having an outlet at its front end, and a stack upon the upper side of the boiler reaching from said outlet rearward and having a discharge opening leading directly to the atmosphere at its rear end, said stack having a downwardly and rearwardly extending plate that forms with the contiguous bottom of the stack a contracted outlet, and a chamber into which said outlet discharges having an outlet above said plate, and a horizontally extending passage above said plate leading from the front of the stack to take air and to pass it rearward into the stack.

4. The combination of a boiler having an outlet at its front end, a stack comprising a successive series of chambers and extending rearward on the outside of the boiler with a discharge opening at its rear end, and a controllable air passage leading into the stack at a point in rear of the front thereof.

5. The combination of a boiler having an outlet at its front end, a stack comprising a successive series of chambers and extending rearward on the outside of the boiler with a discharge opening at its rear end, and a controllable pressure-relieving passage between one of said chambers and another.

6. The combination of aboiler having an outlet at its front end, a steam exhaust commu'nicating with :said outlet, and a stack leading rearward on the outside of the boiler from said outlet and comprising a series of successive chambers, the last 'one of which has a discharge at the rear of the stack that opens directlyto the atmosphere external to the boiler.

7. A spark sarrester having a front chamher, a chamber in rear thereof and a stack chamber and provided with means for 'delivering sparks or cinders to a receptacle and with an inlet pipe.

8. A boiler having a spark arrester arranged "thereon, the spark arrester comprisa front chamber, a stack chamber, a chamber intermediate the stackoha'mber and front chamber, a pressure relief pipe leading from the intermediate chamber and the stack chamber and :a valve or damper controlling the same.

9. A spark arrester having'an air inlet pipe for creating a draft therein and means controlling said air inlet pipe, substantially as set forth, the spark arrester having a pipe leading from'ithe lowerfcharnber to the top Copies 'of'this patent may be obtained mchamber for increasing the draft through the top chamber and for relieving pressure in the lower chamber.

10. The combination of a boiler having an outlet at its front end, and a stack compris ring a chamber in communication with said outlet at its front end and extending rear- Ward therefrom and having an outlet at its rear rendysaid chamber and the portion of the stack rearwardly thereof being carried 7 downward over each side of the boiler.

11. The combination of a boiler having an outlet at Its front end, and a stack comprismg a forward chamber in communication with said outlet at its front end and having have hereunto set my hand.

7 CHARLES W. 'CROWE'LL.

Witnesses:

0. C. BRUTAN, JOHN A. Monnon.

five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

